Examination of physical activity in adolescents over the school year.

This study monitored the physical activity behavior of adolescent students over a ten month school year. Physical activity was assessed at two month intervals using self-report and objective (Actical accelerometers) measures. Self-report results (n = 547) indicated a decline in physical activity throughout the school year for all grades and genders. The decline was attributed largely to a decrease in organized activity participation. Objective physical activity results (n = 40) revealed a significant decline in activity in the latter half of the school year (February to June). Declining physical activity was attributed to a decrease in vigorous activity which was consistent across grade and gender. Collectively, the results highlight the importance of promoting consistent opportunities for adolescents to be active throughout the school year.